1. Field of the Invention
This invention is directed to personal environmental protection systems, in general, and, more particularly, to a headgear structure which is worn by an individual in an environment wherein control of filtered air and protection from particulate material is required.
2. Prior Art
There are several types of air flow, filtration and protective systems which are known in the art. Several types of such systems are currently available on the market for use in surgical arenas, in “clean room” environments, or in hazardous/contaminated environments.
Some of the existing systems include hoods, gowns, filters, and the like. In some instances, the air filters are built into the helmet structure and produce a rather clumsy, cumbersome headgear unit. Known units frequently include external sources of air such as gas cylinders, air lines or the like which are connected to the helmet structure by tubes, hoses or the like. The hose-connected systems, and the long gowns or hoods tend to become extremely cumbersome as well as restrictive of the movements and flexibility of the wearer during a procedure.
Currently available lens/facial seal combinations, sometimes known as loose fitting hoods, are expensive to manufacture due to the geometries required for the facial seal to attach to the lens which is curved in a plane perpendicular to the seal to the face/head of the wearer.
In many of the systems known in the art the hoods and/or gowns are used as filtration devices which have to be replaced frequently. This structure tends, therefore, to become costly inasmuch as the disposable filtration devices are quite expensive.
Moreover, these systems tend to be fairly expensive, especially regarding the disposable portions of the system.
Many such products are known in the prior art. One suitable and functional system is described in U.S. Pat. No. 5,054,480; PERSONAL AIR FILTRATION AND CONTROL SYSTEM, R. O. Bare et al.
Other such systems are described in U.S. Pat. No. 5,711,033; AIR FILTRATION AND CONTROL SYSTEM INCLUDING HEADGEAR; L. J. Green, et al, and in U.S. Pat. No. 6,918,141; PROTECTIVE HEADGEAR SYSTEM; Lawrence J. Green et al.
Another related prior disclosure is described in co-pending application PROTECTIVE HEADGEAR SYSTEM WITH FILTER PROTECTION; Ser. No. 11/442,402; L. J. Green, filed May 30, 2006.